gpu: nvgpu: add __must_check to gk20a_busy

The return value of gk20a_busy must be checked since it may not succeed
in some cases. Add the __must_check attribute that generates a compiler
warning for code that does not read the return value and fix all uses of
the function to take error cases into account.

Bug 200040921

Change-Id: Ibc2b119985fa230324c88026fe94fc5f1894fe4f
Signed-off-by: Konsta Holtta <kholtta@nvidia.com>
Reviewed-on: http://git-master/r/542552
Reviewed-by: Terje Bergstrom <tbergstrom@nvidia.com>
Tested-by: Terje Bergstrom <tbergstrom@nvidia.com>

1 files changed, 7 insertions, 2 deletions

diff --git a/drivers/gpu/nvgpu/gk20a/debug_gk20a.c b/drivers/gpu/nvgpu/gk20a/debug_gk20a.c
index f41d883f..2cc3d38d 100644
--- a/drivers/gpu/nvgpu/gk20a/debug_gk20a.c
+++ b/drivers/gpu/nvgpu/gk20a/debug_gk20a.c
@@ -166,9 +166,14 @@ void gk20a_debug_show_dump(struct platform_device *pdev,
         struct gk20a *g = platform->g;
         struct fifo_gk20a *f = &g->fifo;
         u32 chid;
-        int i;
+        int i, err;
+
+        err = gk20a_busy(g->dev);
+        if (err) {
+                gk20a_debug_output(o, "failed to power on gpu: %d\n", err);
+                return;
+        }
 
-        gk20a_busy(g->dev);
         for (i = 0; i < fifo_pbdma_status__size_1_v(); i++) {
                 u32 status = gk20a_readl(g, fifo_pbdma_status_r(i));
                 u32 chan_status = fifo_pbdma_status_chan_status_v(status);